Paris -LRB- CNN -RRB- -- France 's first lady is filing a defamation complaint against the authors of a biography published Thursday which claims she had an affair with a former French minister while seeing President Francois Hollande .

Attorneys for Valérie Trierweiler , who is not married to Hollande , told CNN the complaint is likely to be filed Friday with the Paris tribunal .

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In `` La Frondeuse , '' or `` The Troublemaker , '' authors Alix Bouilhaguet and Christophe Jakubyszyn allege that Trierweiler had a longstanding relationship with Patrick Devedjian , a former minister for economic recovery and close ally of former President Nicolas Sarkozy .

This relationship allegedly started in 1998 and ended only in 2004 -- four years after her courtship with Hollande began . All of them had other partners at the time .

Trierweiler 's relationship with Devedjian crumbled after he was unable to commit further to their relationship , the book says -- paving the way for Hollande to step in .

Several books have been published about Hollande and his romantic partners since he was elected .

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`` Trierweiler is an interesting subject matter because she has character , '' Bouilhaguet told CNN . `` It 's complicated for a 47-year-old woman to find herself in the Elysée , which has demanding protocol for their first ladies . ''

Bouilhaguet admitted that she was `` surprised '' by the defamation complaint , adding that the book is an `` open investigation with a true look '' at Trierweiler 's personality .

In another extract in the book , the authors write that Trierweiler claims Sarkozy made a pass at her at a July 14 celebration in the Elysée Palace , while holding his ex-wife Cecilia 's hand . `` You 're so beautiful , '' he is said to have whispered in her ear .

When she refused his advances , the book says , Sarkozy said to his friends : `` Who does she take herself for ? Am I not good enough for her ? ''

Trierweiler is characterized by this `` abrupt iciness , '' the authors claim , and inside journalist circles at French newspaper Le Monde , she was labeled `` Cruella . '' A friend of the couple goes even further and says in the book that Trierweiler is the `` Achilles heel '' of Hollande , who can `` potentially create a lot of problems for him . ''

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The authors also called the French first lady a `` narcissistic woman , using at once her charms to get what she wants and in the following second , showing her fangs when something displeases her . ''

Hollande 's complex love life -- including alleged animosity between Trierweiler and Segolene Royal , with whom he has four children -- was the subject of two books published this summer . A poll in August suggested that it was at the root of his sliding popularity .

Trierweiler was embroiled in controversy in June after she tweeted support for Royal 's opponent during the French parliamentary elections .

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A new book says France 's first lady began seeing Hollande while dating another man

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Valérie Trierweiler is known for her strong character

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The book says Sarkozy also made a pass at Trierweiler , who is not married to Hollande